Single line bug in CanTalonSRX::GetAnalogInVel().  return value was not being sign-extended.
Single line bug in CanTalonSRX::GetAnalogInVel().  return value was not being sign-extended.

Change-Id: I44271726ece9aaa7b94f35e611f24a18dbb53825

JLLeitschuh/allwpilib,robotdotnet/allwpilib,PeterMitrano/allwpilib,333fred/allwpilib,JLLeitschuh/allwpilib,JLLeitschuh/allwpilib,PatrickPenguinTurtle/allwpilib,RAR1741/wpilib,PeterMitrano/allwpilib,PatrickPenguinTurtle/allwpilib,PatrickPenguinTurtle/allwpilib,333fred/allwpilib,RAR1741/wpilib,robotdotnet/allwpilib,333fred/allwpilib,PatrickPenguinTurtle/allwpilib,JLLeitschuh/allwpilib,PeterMitrano/allwpilib,RAR1741/wpilib,PatrickPenguinTurtle/allwpilib,robotdotnet/allwpilib,robotdotnet/allwpilib,333fred/allwpilib,JLLeitschuh/allwpilib,RAR1741/wpilib,PeterMitrano/allwpilib,RAR1741/wpilib,PatrickPenguinTurtle/allwpilib,PeterMitrano/allwpilib,PeterMitrano/allwpilib,333fred/allwpilib,JLLeitschuh/allwpilib,RAR1741/wpilib,robotdotnet/allwpilib,JLLeitschuh/allwpilib,RAR1741/wpilib,333fred/allwpilib,PatrickPenguinTurtle/allwpilib,robotdotnet/allwpilib,PeterMitrano/allwpilib